Safety device for gas ovens



3 Sheets-Sheet l .Ewan/2507 T. E. FHARES SAFETY DEVICE F'OR GAS OVENS Oct. 13, 1953 Filed April 14, 1949 Oct. 13, 1953 T. E. PHARES SAFETY DEVICE FOR GAS OVES 5 Sheets-Sham 2 Filed April 14, 1949 Lyon/Zim 5 sheets-sheet "s Zul/@Liar A N q 4N M, 1N l e l .w mw

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T. E. PHARES SAFETY DEVICE FOR GAS OVENS Oct. 13, 1953 Filed April 14, 1949 Patented Oct. 13, 1953 2,655,142 SAFETY LDEVICE Fon GAS ovENS Thomas Esta Phares, Shelbyville, Ind., assignor to Chambers Corporation, a corporation of Indiana Application April 14, 1949, Serial No.- 87,547

10 claims. (C1. 126-42)y This invention relates to an ignitiondevice for t ovens in gas-cooking stoves, and'has particular reference to means to prevent ignition of the gas burner when the oven door is closed.

The manual means for igniting the gas burner is generally similar to that described in the copending application of John E. Chambers, Serial No. 72,659, led January 25, 1949 now assigned to the same assignee. It consists essentially of yan electrical circuit closed automatically when the gas valve is opened to produce a spark adjacent the gas burner.

The present invention is concerned primanly with means for preventing the opening of the gas valve when the oven door is closed. This structure is of particular importance in connection with a gas oven because the oven is an enclosed space in which a discharge of unburned gas can create a hazardous explosive m1xture 'with the contained air.

In the oven constructed in accordance with the present invention, the oven bottom plate, wh1ch is located above the burner, has an opening adjacent to its front edge through which the burner vand its flame are plainly visible when the oven door is open. If, for any reason, the gas is not ignited immediately when the valve is opened, the failure of the ignition system is apparent, and the gas can be ignited with a match. The open door precludes the possibility of an explosive mixture with the contained air.

The structure of the present invention by which the above advantages are attained will be described in the following specication, taken in conjunction with a preferred illustrative embodiment shown in the accompanying drawings, in which:

Figure 1 is a cross Sectional view -showing the arrangement of parts when the oven door is closed;

Fig. 2 is a cross sectional view, Similar to Fig. l, showing the arrangement of parts when the door is open;

Fig. 3 is a fragmentary cross sectional view Showing the bottom portion of the oven door and .the associated stove structure;

Fig. 4 is a fragmentary cross Sectional view of the upper portion of the oven door and the mechanism for controlling the oW of gas; Fig. 5 is a cross sectional view taken along the line 5-5 of Fig. 4, showing the mechanism for holding the gas control valve against rotation; vand Fig. 6 is a diagrammatic perspective View of :the l,safety lock bar and associated mechanism,

Vnected to the gas valve Il.

In the drawings, the reference numeral 2 indicates the outside steel front of the gas cooking stove. The front opening of the oven is closed by an insulated door 3 secured'in closed position by a latch 4. The catch member 5 has a Stem A6 projecting through front 2 and secured to the upper portion of a flat plate I by means of a `nut 8 threaded on the stem. The plate covers the entire area of the front of the oven and has an opening aligned with the opening in front Wall 2. The lower edge of plate 1 is secured to a plate 9 forming the bottom of the oven. A pair of vertically aligned studs I0 is Secured to plate 1 with their headed ends projecting towards the .front of the stove. A safety lock bar I I provided with a pair vof elongated slots I2 is mounted in front of plate I With one slot I2 embracing each stud I0.

The top edge of bar II is bent rearwardly at right angles, as indicated at I3, and a plate I4 secured thereto has its free end engaging an abutment I5 formed on the edge of a disk I6 rigidly mounted on a shaft I'I operatively con- Shaft I'I including disk I6 must be rotated to open the gas control valve and thus permit the ilow of gas to the oven burner. Disk I6 has a notch I8 on its edge opposite abutment I5.

As described in the co-pending Chambers application hereinabove identified, a housing I9 seats in notch I8 and prevents disk I6 and shaft Il from rotating. Tilting of the housing by application of thumb pressure on the lever I9 serves to move it out of engagement with the notch and permits rotation of the shaft. The housing carries a contact member 20' which serves to close a Switch 20 upon movement of the housing slightly beyond the region of its engagement with the notch. When the switch is closed an electrical circuit 22 is energized and a spark is produced adjacent the oven gas burner 23. The spark ignites the burner and the electrical circuit is then opened by releasing the tilting pressure on the housing.

The safety lock bar II carrying plate I4 prevents ignition of the burner when the oven door is closed by engagement of the plate with abutment I5, because the plate vcannot be removed from such engagement without opening the oven door. While the oven door is closed, the engagement of plate I4 with abutment I5 prevents rotation of shaft I'I to move the gas control valve from closed position, and thereby prevents the flow of gas to the burner.

The lower edge of door 3 is hinged adjacent the bottom of the front opening of the oven, as indicated at 24. A door stop 25 is secured at its upper end 26 to the inside of the door, and its lower end 21 is pivotally secured to an oven door stop rod 28. Rod 28 extends through oven bottom 9 almost to the bottom of front plate 2. A coiled compressionspring 29 encirclesrod 28 below bottom 9, jnd isetaind en the,Y rod by means of a nut 30 and washer 3|. When the oven door is opened the lower end 21 of stop 25 moves upwardly, as indicated in Eig. 2, thereby pulling up the rod and compressing 29. The spring will not close the oven door by itself but win assisi in closing iiaia will noia it iii closed position.

Door stop 25 has its outer edge 3| cam shaped, so that the portion engaging th-:bottom 'edge of safety lock bar ll when the door is closed (as shown in Fig. 1) is at a greater height abbv ,themen iasiitom. menthe Portion engaging. ii niet trie Mdei is iiiin infial2). the over; indi 'is fbi ,erige isi :keeps )'jar .'Il 'in itslfuppernibst po tin, 'in V"which po;- ns itlonI 'plate @1,4 engages aidu ment i 5 tto rreveiit rg'itaiicii jiA Idisk f s, therapy fiaking it iin-'posa 'sible to 'turn 'on the ,gasA jWhen Athe joven Hebr is "openedgcainsriace 3 I `Vzierixriits bar H to l slide d'wn,vx and plate '1 4 Jdrops 'oit l"fof engagement ih. abnimmt 515 so thai esk 1.16 im iie Y, i vtoeinen fiieigaisfoiii'rdi ifa/ige. slots i2. which S'exynb'racfe fstiids l l), permit "su'iiicie'n't "movenient 'in thefsafety Lbei "tofcla'r abutment l l 5.

gas'is turned on. The 'Xactdeg'ree ofopening iin tion of disk i6. The other end of bell crank 42 is secured to a second damper control rod 45. 'Ihe other end of rod 45 is secured to a link 4B which is secured to damper 38. When rod 38 Imoves bell crank 42 to open damper 3T, rod 45 moves link 46 to open damper 38. When damper 31 is closed, damper 38 .is also closed. From the foregoing itiwill be seen that I have devised simple and eiicient means for prevent- `ing ignition of an oven gas burner when the Y oor is closed and for visually observing the when the door is open, thereby providing an ,ample factor of-safety for igniting gas oven Brgers Although l have described a preferred embodimentmof Ymy invention in considerable detail, it Will be 'inderstood that the description thereof is *intended to be illustrative, rather than restrictive, as many details may be modified or changed without departing from the spirit or scope 'of the invention. Accoringy, I do not desire "to be restricted "to 'the leiract structure described.

I claim: '1. 'In an loven, aig'as burner, `a valve-ibtatable tb contrl th'ew "Gigas -t'o saidlburner, vfailiisk ro'tatable vv'v'ithfs'aid valve, -a safety look bar Vslidable iin a `vertical direction, said 5bar when iin its lupperiifdst'psition engaging said-'fdisk aciprevefrit rtjtinefjsaid va1v e from-closed position, a hinged door 'aacent the Y"front 'of 'said nve'n, a door` stop movable with s'aid llioor, fone edge f sai'cl door "s t'op 'being carrrsliaped fthe YloWeI` end -f Ls`ad"saf'e"ty 'lock bar vengaging-"said cam-shaped 'elige topcsitic'm 'said -bar, said'fcam.. shaped edge Holding said 'b'arin its -1ppermost position when said ddris closed.

2. -In an oven, "a doo'r, "a gas burner, la "valve rotatableto 'zi'tr'ol'tlieJ ilovvof'gasito saidburner, adisk rotatable with said"valve,"`sa'id*disk hav- I-ingan Aab'utr'nrlt lprjecting therefrom, asafety lock bar engaging said abutment 'to' prevent rotatin of *said vlvejwhn s'aidfvalve"andsaid door arem closed, "said safety 'locking bar being l-rariovable `from engagement Y with said "abutment only upon movement of said-door to open position-and a door-stop secured'to 'said door,"said door step-having @an -upper'edgein the shape "'f afnam,fsaideupperfedgeengaging-the lower end o'f said locking bar andoperable-tomove said safety 'lo'clnngfflcar upwardly when saiddooris moved Ito l'closed :position i whereby -sa-id v-barwlill` engage fsaidabntment Whensaidvalveis rotatedto closed `position.

3.111 iiaigas i cooking-stove, ianl oven, :aadoor hinged to said stove adjacent the front ofssaid fcven, f'aidorfistop movable "with isaid-I door,I :said vdoera'stop .having aficlamshapedv edge; afsafety lock bar mounted to slide in a vertical plane-1intersectingiitlieiplanefofsaid-'door stop, the xlower 'edge-'ofi' said bar'r'estingl lon fsaid cam-shapedredge of said door stop whereby said bar is :moved 'betwen'npprllanda lower? position as f'said ld'erii'sinvdletweenIelosedand open position, a gas burner in said lieven,2 a 'valvei controlling vifh'e"filtwixiifgas'toesaid'ilziuiifner;and a diskrotat- -ablef-with fsaidY-valve'theIupperendaofffsaid :bar engaging said'dsk iwhenfsaidfbar-fisllin 'itsI-upper -po'stionf f and fsaidi gas 1 'control valve Lis` in its on' iposition i t'o :'fprevent rotation-I of :said fdisk :and `therebyprevent iturningiofirsaid gas oontrol'valve from its oif position when said oven door is closed.

the portion of said stop member adjacent the front of said oven being positioned at a greater height above the bottom of said oven when said door is closed than when it is open, a safety lock bar operatively connected to said stop member, and a gas control valve for said oven, said valve including a manually operable means for opening and closing said valve, said bar being slidably mounted in a plane adjacent the front of said oven with its lower end riding on said stop member, said bar interengagingwith said manually operable means for preventing opening of said gas control valve when the lock bar is in its uppermost position, to prevent the opening of the gas control valve.

5. In a gas cooking stove, an oven having a hinged door, a gas burner in said oven, a gas control valve for said burner, said valve including a shaft rotatable to regulate the ow of gas to said burner, a disk rigidly secured to said shaft and rotatable therewith, a peripheral abutment on said disk, a safety lock bar engageable with said abutment to prevent rotation'of said disk when said valve is closed, and a door stop having an upper cam shaped edge engaging the lower end of said lock bar, said door stop being operatively connected to said door to hold said bar in said abutment-engaging position when said door is closed.

6. In a gas cooking stove, an oven having a hinged door, a gas burner in said oven, a gas control valve for said burner, said valve including a shaft rotatable to regulate the 110W of gas to said burner, a disk rigidly secured to said shaft and rotatable therewith, a peripheral abutment on said disk, a safety lock bar engageable with said abutment to prevent rotation of said disk when said valve is closed, and a door stop connected to said door, said door stop engaging said bar to prevent its disengagement from said abutment when said door is closed.

7. In a gas cooking stove, an oven having a hinged door, a gas burner in said oven, a gas control valve for said burner, said valve including a shaft rotatable to regulate the flow of gas to said burner, a disk rigidly secured to said shaft and rotatable therewith, a peripheral abutment on said disk, a safety lock bar engageable with said abutment to prevent rotation of said disk when said valve is closed, a door stop movable with said door, said door stop engaging said bar to prevent its movement from said abutmentengaging position when said door is closed, and a spring urging said bar downwardly, said door stop being so shaped as to permit said bar to move downwardly out of engagement with said abutment when said door is moved to open position.

8. In a gas cooking stove, an oven, a door for said oven, a door stop movable with said door and extending at right angles thereto, a plurality of dampers in said oven, a gas burner in said oven, a valve rotatable to control the fiow of gas to said burner, said valve including a shaft rotatable to regulate the flow of gas to said burner, a disk operatively connected to said shaft and rotatable therewith, a safety lock bar engaging said door stop and held thereby against said disk to prevent rotation thereof from closed position when said door is closed, and a rod operatively connected with said disk and said dampers, said rod opening said dampers when said disk is rotated from closed to open position.

9. In a gas cooking stove, an oven, a door for said oven, a door stop movable with said door and extending at right angles thereto, a pluraliy of dampers in said oven, a gas burner in said oven, a valve rotatable to control the ow of gas to said burner, said valve including a shaft rotatable to regulate the flow of gas to said burner, a disk operatively connected to said shaft and rotatable therewith, a safety lock bar engaging said door stop and held thereby against said disk to prevent rotation thereof from closed position when said door is closed, said door stop being so shaped as to permit said bar to move from disk-engaging position when said door is opened, and means operated by rotation of said disk to open and close said dampers.

10. In an oven, a gas burner, a valve rotatable to control the flow of gas to said burner, a disk rotatable with said valve, a safety lock bar slidable in a vertical plane, said bar'having a lateral extension at its upper end engaging said disk to prevent rotation of said valve from closed position when said bar is in its uppermost position, a hinged door adjacent the front of said oven, and a door stop movable with said door, one edge of said door stop being cam-shaped, the lower end of said safety lock bar engaging said cam-shaped edge to position said bar, said cam-shaped edge holding said bar in Iits uppermost position when said door is closed.

THOMAS ESTA PHARES.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 910,301 Mills Jan. 19, 1909 1,049,588 Mersfelder Jan. 7, 1913 1,068,230 Ellis July 22, 1913 1,087,886 Mirrielees Feb. 17, 1914 2,212,875 Camp Aug. 27, 1940 2,337,301 Phares Dec. 21, 1943 FOREIGN PATENTS Number Country Date 512,335 Great Britain Sept. 1, 1989 

